Crayfish plague in Haldenvassdraget

The Natinal Veterinary Institute has diagnosed crayfish plague on European crayfish at Øymark lake in Haldenvassdraget. The crayfish was encaged in the water as part of a monitoring program. The disease has previously been diagnosed in Haldenvassdraget in 1989 and 2005. Crayfish plague is considered a serious threath to the Norwegian stock of European crayfish.